Feinstein: Obama didn't flip-flop on gay marriage

5/13/12 9:18 AM EDT

"I don't think it's a flip-flop. There's no political calculus because it's not smart," Feinstein said on "Fox News Sunday." "If he's going to do it from a political point of view, it doesn't make any sense."

Feinstein said she's undergone an evolution similar to Obama's.

"It also happened to me. You get to know more and more gay couples. You see the happiness. You see the economic security that marriage brings and even more fundamentally you see children who otherwise would not have an adopted home being able to have that home," she explained. "So same sex couples raise children, they do a fine job…More and more people say what's wrong with people being happy?"